Some matches are defined by one key shot or rally. Roger Federer’s 2-6, 7-6 (6), 6-1 win over Jo-Wilfried Tsonga in Monte Carlo on Friday was defined by one key stat: Federer’s break-point conversion rate. He was two of 19.

Over the course of the first two sets, Tsonga always seemed to be serving; and every time you turned around, he was facing another break point. At one stage late in the second set, Jo had served 68 points, while Federer had served exactly half that many at 34. The pattern was the same throughout: Federer would come up with something brilliant—a topspin lob winner, a flick backhand pass, a strong forehand down the line—to reach break point, and then Tsonga would wipe it away.

Federer’s break points turned into a chess match, as Jo came up with different ways to survive them. He used his wide kick serve to draw short returns from Federer, and when that became predictable, he sent a surprise bomb down the T. Between them, the two players found a seemingly infinite variety of ways to keep Federer from breaking. Federer flipped a short backhand into the net. He shanked a backhand pass wide. He chose the wrong direction with an easy forehand pass. Jo knocked off a down-the-line forehand. He rifled a service winner. He wedged an inside-in forehand approach into the corner on one point, then wedged one inside-out on the next. Early in the second set, after Federer knifed a slow second-serve return into the bottom of the net, he shook his head and smiled sarcastically. Two games later, he bashed a ball out of the stadium and received a rare warning from the chair umpire.

The odd thing was that while Tsonga spent the match perpetually teetering on the brink, he very nearly won it in straight sets. Up 6-2, 3-2, Jo reached break point on Federer’s serve. But he backed up on a backhand and put it in the net. Twenty minutes later, after saving three more break points, Tsonga went up 0-30 on Federer’s serve at 5-6—two more points and it was over. At 0-30, Jo took a big cut at a forehand and landed it near the baseline, but Federer was there to reflex it back on the short hop; Tsonga’s next forehand went astray. At 15-30, Federer shanked a forehand that dropped inside the baseline, and clipped the net cord with another forehand, before winning the point, and eventually the game.

Finally, in the second-set tiebreaker, Tsonga saved three set points from 3-6 down, only to pull the trigger too early at 6-6 and fire a forehand into the net. When Federer won the next point, and the set, with a forehand volley, the crowd stood. Jo, understandably, slumped.

From there, it felt like it was only a matter of time before Federer broke through and Tsonga broke down. It happened quickly, in Jo’s second service game. He managed to save break points number 14 and 15, but not number 16—a forcing inside-out forehand approach from Federer made sure of that. Tsonga threw up a backhand lob that landed long. He might as well have been throwing up a white flag.

Aggressive but erratic, Federer hit 40 winners, made 45 errors, and was 21 of 28 at the net. His excellence in tiebreakers saved him from his dismal break-point percentage. He got angry, but he never went away. Persistence, rather than prettiness, pulled Federer through today.